FINAL ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Arguments
Applicant's arguments filed 25 November 2025 have been fully considered but they are not persuasive.
In response to Applicant’s assertion that “the inlet area of the Kjӕr centrifuge is formed on the solids discharge side section and not, as now more specifically defined by amended Claim 1, between two closed wall structures of the cylindrical longitudinal section of the screw hub” (page 9, Remarks), the examiner respectfully disagrees. Kjӕr teaches the open wall structure (broad mutually spaced ribs 39 in the first axial area 49, Fig. 1 and 2) is spaced from the portion at the solid-discharge end 37, wherein the open wall structure is designed between a first portion of a closed wall structure and a second portion of a closed wall structure as discussed in the rejection below.
In response to Applicant’s argument that “the inlet area of the centrifuge disclosed in Kjӕr has neither the claimed opening proportions nor the claimed maximum longitudinal extensions of the fastening or connecting areas, as now recited in amended Claim 1” (page 9, Remarks), the examiner notes that the numerical limitations relating the maximum longitudinal extension of the attaching or connecting areas (20%) and the proportion of openings in the radial direction (at least 65%) are obvious design choices within the geometry already disclosed by Kjӕr, which includes ribs forming openings, an axial region with the openings, and the ribs attached to adjacent hub portions. Within such a structure, one of ordinary skill in the art would inherently determine how wide the ribs are, how large the openings are, and how long the rib attachment regions extend, which would necessarily determine the proportion of openings and the longitudinal extension of the attachment regions relative to the total larger outer diameter portion. Kjӕr also describes the ribs 39 as “broad mutually spaced ribs” (para. [0027]), and the spacing between the ribs shown in Fig. 2 indicates that the open area makes up the majority of the wall area. Without a demonstration of criticality, the values 20% and 65% are treated as arbitrary selection of dimensions. Such unsupported limitations cannot be a basis for patentability, since where patentability is said to be based upon particular chosen parameters or upon another variable recited in a claim, the applicant must show that the chosen dimensions are critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990) and MPEP 2144.05(III). The specification of the present application itself indicates that the claimed dimensional relationships are selected to balance structural rigidity and flow characteristics (page 5 lines 10-13, page 8 lines 3-8, specification as filed), which are routine optimization engineering design considerations, rather than demonstrating critical dimensions. Applicant has not provided evidence that the claimed numerical relationships represent a critical threshold producing an unexpected result. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum or workable ranges by routine experimentation. In re Aller, 220 F.20 454, 456, 105 USPO 233, 238 (CCPA 1955); In re Swain et al., 70 USPQ 412; Minnesota Mining and Mfg. Co. v. Coe, 38 USPQ 213; Allen et al. v. Coe, 57 USPQ 136; MPEP 2144.05(II)(A). Thus the selection of particular dimensional proportions including wherein the longitudinal extension of the respective (single) attaching or connecting areas is maximally 20% of the total longitudinal extension of the area having a larger outer diameter (DW), and wherein the proportion of openings in the radial direction of the screw hub is at least 65% of the total wall structure in the radial direction, are obvious design choices for one of ordinary skill in the art.
Applicant argues that “Kjӕr provides a feed accelerator 59 to accelerate the material to be processed into the separation chamber via the inlet area. Thus, the Kjӕr reference addresses the feed of the material to be processed into the interior of the drum and not an open wall structure defined by amended Claim 1” (page 10, Remarks). This argument is not persuasive. Applicant’s characterization of the ribbed open wall region of Kjӕr as part of a feed accelerator does not distinguish the claimed invention over Kjӕr. The claim recites structural features of the screw hub, and does not require the open wall structure to serve a particular operational purpose. Even if the openings of Kjӕr are used to facilitate feed entry or acceleration, the structure of the hub wall in that region teaches the same structural configuration recited in the claim.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Drawings
The drawings were received on 5 May 2023. These drawings are acceptable.
Specification
The specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant's cooperation is requested in correcting any errors of which applicant may become aware of in the specification.
The abstract of the disclosure is acceptable.
The title of the invention is acceptable.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-3, 5, 6, 9, 12 and 13 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 1, the phrase “wherein the longitudinal extension of the respective (single) attaching or connecting areas is maximally 20% of the total longitudinal extension of the area having a larger outer diameter (DW)” is indefinite, because it is unclear if the 20% limit applies to each attaching or connecting area or the total of both attaching or connecting areas. Claims 2, 3, 5, 6, 9, 12 and 13 are rejected for the same reason due to their dependency upon said claim.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claims 1-3, 5, 6, 9, 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Kjӕr (U.S. Patent Application Pub. No. 2012/0157289).
Regarding claim 1, Kjӕr discloses a centrifuge screw (screw conveyor 5, Fig. 1) having a screw hub (33, Fig. 1) and a screw spiral (helical conveyor flight 41, Fig. 1) connected to the screw hub, wherein the screw hub in the longitudinal direction has at least one cylindrical longitudinal portion (cylindrical part 35, Fig. 1) and a portion at the solid-discharge end (conical part 37, Fig. 1), characterized in that in the cylindrical longitudinal portion, an open wall structure (broad mutually spaced ribs 39 in the first axial area 49, Fig. 1 and 2) is designed only in sections, wherein the open wall structure extends in the cylindrical longitudinal portion at most over a length of 50% of the total length of the cylindrical longitudinal portion (Fig. 1 clearly shows the broad mutually spaced ribs 39 in the first axial area 49 to extend much less than half of the total length of the cylindrical portion, see Fig. 1 and 2), the open wall structure is spaced from the portion at the solid-discharge end (see annotated Fig. 2 below), wherein the open wall structure is designed between a first portion of a closed wall structure and a second portion of a closed wall structure (see annotated Fig. 2 below), wherein the open wall structure has a larger outer diameter (DW) than neighboring portions of the screw hub (Fig. 1 and 2), wherein for attaching or connecting the open wall structure to the neighboring portions of the cylindrical longitudinal portion, the increased outer diameter is also designed at the respective adjacent ends of the neighboring portions of the cylindrical longitudinal portion (see annotated Fig. 2 below), but does not explicitly disclose wherein the longitudinal extension of the respective (single) attaching or connecting areas is maximally 20% of the total longitudinal extension of the area having a larger outer diameter (DW), wherein such a wall structure of the screw hub has to be understood to be an open wall structure which has a high proportion of openings in the radial direction, wherein the proportion of openings in the radial direction of the screw hub is at least 65% of the total wall structure in the radial direction.
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However, the numerical limitations relating the maximum longitudinal extension of the attaching or connecting areas (20%) and the proportion of openings in the radial direction (at least 65%) are obvious design choices within the geometry already disclosed by Kjӕr, which includes ribs forming openings, an axial region with the openings, and the ribs attached to adjacent hub portions. Within such a structure, one of ordinary skill in the art would inherently determine how wide the ribs are, how large the openings are, and how long the rib attachment regions extend, which would necessarily determine the proportion of openings and the longitudinal extension of the attachment regions relative to the total larger outer diameter portion. Kjӕr also describes the ribs 39 as “broad mutually spaced ribs” (para. [0027]), and the spacing between the ribs shown in Fig. 2 indicates that the open area makes up the majority of the wall area. Without a demonstration of criticality, the values 20% and 65% are treated as arbitrary selection of dimensions. Such unsupported limitations cannot be a basis for patentability, since where patentability is said to be based upon particular chosen parameters or upon another variable recited in a claim, the applicant must show that the chosen dimensions are critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990) and MPEP 2144.05(III). The specification of the present application itself indicates that the claimed dimensional relationships are selected to balance structural rigidity and flow characteristics (page 5 lines 10-13, page 8 lines 3-8, specification as filed), which are routine optimization engineering design considerations, rather than demonstrating critical dimensions. Applicant has not provided evidence that the claimed numerical relationships represent a critical threshold producing an unexpected result. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum or workable ranges by routine experimentation. In re Aller, 220 F.20 454, 456, 105 USPO 233, 238 (CCPA 1955); In re Swain et al., 70 USPQ 412; Minnesota Mining and Mfg. Co. v. Coe, 38 USPQ 213; Allen et al. v. Coe, 57 USPQ 136; MPEP 2144.05(II)(A). Thus the selection of particular dimensional proportions including wherein the longitudinal extension of the respective (single) attaching or connecting areas is maximally 20% of the total longitudinal extension of the area having a larger outer diameter (DW), and wherein the proportion of openings in the radial direction of the screw hub is at least 65% of the total wall structure in the radial direction, are obvious design choices for one of ordinary skill in the art.
Regarding claim 2, Kjӕr discloses that the open wall structure in the cylindrical longitudinal portion extends at most over a length of 45% of the total length of the cylindrical longitudinal portion (Fig. 1 clearly shows the broad mutually spaced ribs 39 in the first axial area 49 to extend less than a quarter of the total length of the cylindrical portion, see Fig. 1 and 2).
Additionally, regarding claims 1 and 2, it would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to have selected the length of the open wall structure to be at most over a length of 50% or 45% of the total length of the cylindrical longitudinal portion. Kjӕr teaches that the open wall structure is configured to provide an inlet chamber or acceleration chamber, and varying its length within predictable ranges to achieve a proper balance between the inlet/acceleration chamber and the rest of the cylindrical longitudinal portion which defines the separation chamber is considered routine optimization.
Regarding claim 3, Kjӕr discloses the open wall structure (broad mutually spaced ribs 39 in the first axial area 49, Fig. 1 and 2) is designed to be spaced from both ends of the screw hub (broad mutually spaced ribs 30 in the first axial area 49 is located between the cylindrical part 35 and the conical part 37, Fig. 1 and 2).
Regarding claim 5, Kjӕr discloses that the outer diameter of the open wall structure (as defined by ribs 39, Fig. 1 and 2) is smaller than the outer diameter of the screw spiral (as defined by helical conveyor flight 41, see Fig. 1 and 2), but does not specifically teach that a ratio of a/the outer diameter of the open wall structure of the outer diameter of the screw spiral is 0.8-0.4. Kjӕr teaches that the feed ports are defined by the mutually spaced ribs 39, which provides an open construction with a minimum of disturbance of the flow of feed material from the discharge outlet to the surface of material in the separation chamber (para. [0014]) and the helical conveyor flight 41 transports heavy phase towards the heavy phase outlet opening (para. [0027]). It would have been obvious for one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the ratio between the outer diameter of the open wall structure to the outer diameter of the screw spiral of Kjӕr to be in the claimed ranges, for the purpose of varying the ratio within predictable ranges to achieve a desired combination of feed distribution, mechanical strength of the open wall structure, separation efficiency, minimize turbulence, or other process conditions, which are considered at most optimum choices, lacking any disclosed criticality.
With respect to the limitations of the parameter regarding the length of the open wall structure and the ratio between the outer diameter of the open wall structure to the outer diameter of the screw spiral, which are present in the claims at issue, the examiner has found that the specification contained no disclosure of any unexpected results arising therefrom, and that as such the parameters are arbitrary and therefore obvious. Such unsupported limitations cannot be a basis for patentability, since where patentability is said to be based upon particular chosen parameters or upon another variable recited in a claim, the applicant must show that the chosen dimensions are critical. In re Woodruff, 919 F.2d 1575, 1578, 16 USPQ2d 1934, 1936 (Fed. Cir. 1990) and MPEP 2144.05(III).
Applicant has the burden of proving such criticality. In re Swenson et al., 56 USPQ 372; In re Scherl, 70 USPQ 204. However, even though applicant's modification may result in great improvement and utility over the prior art, it may still not be patentable if the modification was within the capabilities of one skilled in the art. In re Sola, 25 USPQ 433; In re Normannet et al., 66 USPQ 308; In re Irmscher, 66 USPQ 314.
More particularly, where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover optimum or workable ranges by routine experimentation. In re Aller, 220 F.20 454, 456, 105 USPO 233, 238 (CCPA 1955); In re Swain et al., 70 USPQ 412; Minnesota Mining and Mfg. Co. v. Coe, 38 USPQ 213; Allen et al. v. Coe, 57 USPQ 136; MPEP 2144.05(II)(A).
No probative evidence is of record to demonstrate that the length of the open wall structure, the ratio between the outer diameter of the open wall structure to the outer diameter of the screw spiral, and/or other variables of the invention are significant or are anything more than one of numerous dimensions a person of ordinary skill in the art would find obvious for purposes of merely changing the configurations and/or dimensions to obtain different results. Graham v. John Deere Co., 148 USPQ 459. Accordingly, the examiner argues that these parameters are rather arbitrary and thus obvious over the prior art per MPEP 2144.05(II)(III).
Furthermore, the Federal Circuit has explained that a reason to optimize prior art parameters may be found in a PHOSITA’s desire to improve on the prior art. In re Ethicon, Inc., 844 F.3d 1344, 1351 (Fed. Cir. 2017) (“The normal desire of artisans to improve upon what is already generally known can provide the motivation to optimize variables such as the percentage of a known polymer for use in a known device.”’).
Regarding claim 6, Kjӕr discloses the open wall structure is formed so as to have several longitudinal rods (ribs 39, Fig. 1) running in the longitudinal direction.
Regarding claim 9, Kjӕr discloses the portion (conical part 37, Fig. 1) at the solid-discharge end (heavy phase outlet openings 15, Fig. 1) has a cone shape or a double truncated cone shape (Fig. 1).
Regarding claim 12, Kjӕr discloses a solid bowl screw centrifuge (decanter centrifuge 1, Fig. 1) comprising a centrifugal screw (screw conveyor 5, Fig. 1) located within a drum (bowl 3, Fig. 1), wherein the centrifugal screw is designed according to claim 1.
Regarding claim 13, Kjӕr discloses the open wall structure is designed to be a middle segment (broad mutually spaced ribs 30 in the first axial area 49 is located between the cylindrical part 35 and the conical part 37, Fig. 1).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHUYI S LIU whose telephone number is (571)272-0496. The examiner can normally be reached MON - FRI 9:30AM - 2:30PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Claire Wang can be reached at 571-270-1051. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Shuyi S. Liu/Examiner, Art Unit 1774
/CLAIRE X WANG/Supervisory Patent Examiner, Art Unit 1774